An Indian start-up company has a plan for fighting one of the biggest killers of children worldwide, one that weaves together a centuries-old artisanal craft with the high-tech power of a “lab-on-a-chip.”

Achira Labs received $100,000 in Canadian funding this week to pursue its plan to develop a strip of silk that can diagnose deadly viruses. If all goes well, their elegant innovation will some day end up exactly where they want it: inside a diaper.

On Thursday, Grand Challenges Canada, a non-profit funded by the Canadian government, announced $9.3 million in grants for 83 projects aimed at improving health in the developing world.

The projects — 14 are based in Toronto — target health issues in 30 countries and include everything from a cellphone app for detecting breast cancer to mosquito-repellent shoes that can help prevent diseases like malaria and dengue fever.

One grant is going to Bangalore’s Achira Labs, a four-year-old biotech company co-founded by Dhananjaya Dendukuri, who studied chemical engineering at the University of Toronto and MIT.

Dendukuri and his team want to tackle rotavirus — a common cause of diarrhea that is still the world’s second biggest killer of children under 5.

The toll is especially high in developing countries, where many people cannot afford or access the rotavirus vaccine. In 2008, 22 per cent of children under 5 who died from rotavirus lived in India, with nearly 99,000 deaths.

Achira biotechnician Paridhi Bhandari, the team’s lead on the rotavirus project, has seen first-hand how dangerous rotavirus can be. Last winter, her cousin’s 1-year-old son caught an infection and became dangerously dehydrated.

“He was passing stool 30 to 40 times in a day,” she said, and this went on for eight days. “You can really lose your child. I saw that myself.”

But for many of India’s poorest, getting a laboratory diagnosis can be prohibitively expensive and test results may take days, potentially delaying treatment. Without knowing the exact diagnosis, doctors may also prescribe antibiotics in case a bacterium is causing the diarrhea — a precautionary move that would prove useless for killing rotavirus and contributes to the problem of antibiotic resistance.

So the team at Achira developed a new diagnostic test, one that is both fast and cheap, by turning to an unexpected source: woven silk, a material Indians have been using for centuries to make saris and other garments.

“We said, ‘What can we find around us that is actually capable of doing this?’ ” Dendukuri explained in a video posted by Grand Challenges. “One of the nice things about textile weaving, in addition to the fact that you can actually gainfully employ skilled artisans … it’s also a very eco-friendly approach. You’re not using plastic, for example.”

But how does a strip of silk diagnose a virus? Bhandari explained that the silk threads are coated with rotavirus antibodies and then woven together into a sheet of fabric using a standard loom. The fabric is then cut into thin strips — each no longer than a credit card — with one sari-sized sheet producing at least 1,000 diagnostic strips.

When a rotavirus-infected stool sample is applied to the strip, then the antibodies can detect the pathogen and trigger a colour reaction, turning the fabric pink in just 15 minutes.

Achira Labs will use its grant to conduct further tests and make sure the strip works. The researchers want to see it used in clinics and hospitals someday but their biggest hope is that diaper manufacturers will put it inside their products — this way, rotavirus infections will be immediately diagnosed right at home.

“That is the exciting part,” said Dr. Durga Rao with the Indian Institute of Science, a rotavirus expert who has teamed up with Achira Labs. “This way, any uneducated person can know what is causing the diarrhea. In India, many of our mothers are relatively uneducated.”

For global health expert Dr. Zulfiqar Bhutta, the co-director of Sick Kids’ Global Child Health centre, Achira’s idea is a “fascinating concept and potentially useful” — especially if the strip can be produced cheaply and eventually repurposed to accurately diagnose other types of diarrhea.

His main concern with the commercial diaper idea, however, is that the people most vulnerable to rotavirus infections probably cannot even afford disposable diapers. Bhandari said her colleagues hope to develop a fabric strip for cloth diapers, too.

“(Diapers) serve the rich and middle classes presently,” Bhutta said in an email. “In the foreseeable future, that will not change and so the bigger challenge for them is to translate a fascinating concept and idea into a workable innovation for the poor and not the rich.”